Commonly assigned (and therefore not necessarily prior art) U.S. patent application Ser. No. 08/057,241, entitled "Side Biased Datum Scheme For Inkjet Cartridge and Carriage" and filed 30 Apr. 1993, discloses an inkjet printer which has a movable carriage supported above an ink receiving medium by a rail defining a carriage axis. Mounted on the carriage is a cartridge holder which has at least one cartridge compartment each receiving a respective ink jet printer cartridge, and which has a leaf spring near the mid-point between the front and rear ends of each compartment for applying a lateral holding force to hold the cartridge laterally against a compartment wall. Each cartridge has an array of nozzles located on a nozzle plate mounted on the lower surface of a snout which, when the cartridge is installed, passes through an opening in the compartment floor located to the rear of the leaf spring. Because the compartment wall is made of compliant material (i.e., plastic) and because the stiffening effect otherwise provided by the floor is eliminated in the vicinity of the snout opening, the rear portion of the compartment wall is more compliant than, and will therefore deflect more than, its front portion.